Prostheses are commonly used in the dental industry for replacing or reconstructing teeth. Generally, such dental prostheses can be in the form of implants, crowns, bridges, onlays and inlays. Since such prostheses have to be designed precisely in order to ensure proper fit, manufacturing methods for such products have to meet certain criteria in terms of accuracy in designing and machining. It is recognized in the art that computer aided design (CAD) and computer aided manufacturing (CAM) can be viable options for providing flexibility, ease and accuracy in designing and manufacturing such prostheses.
For example, U.S. Pat. No. 6,287,121 describes a device for determining the shape of a duplicate of a remaining tooth area to be provided with a dental prosthesis and an arrangement for producing the dental prosthesis. The described arrangement for producing the prosthesis comprises a shape determination device and a machining device for the actual production of the dental prosthesis, and an electronic data processing (EDP) installation. The EDP installation couples the shape determination device with the machining device, and also includes a memory unit for the results of the shape determination device, and a control unit for controlling the machining device. U.S. Pat. No. 6,287,121 primarily relates to a three serial module arrangement consisting of the shape determination device, EDP installation and machining device. All control and monitoring functions take place in the EDP installation, so that the shape determination device and the machining device need not have individual EDP units. This provides central control and monitoring of the entire production of the dental prosthesis at the EDP installation. Such an arrangement may be efficient for cases where only one machining device is needed. However, such an arrangement may prove disadvantageous in terms of efficiency for relatively large scale production of dental prostheses, e.g. in a production lab having a plurality of machining devices connected in a network with various workstations. In such a network, one may have a plurality of machining jobs, each corresponding to a particular dental prosthesis to be machined and may want to have the machining devices run independently with minimal user intervention. Thus, a system and method specifically suited for such applications would be desirable.
WO 01/37756 discloses an arrangement for a system for manufacturing dental products having a plurality of production units. The manufacturing system comprises various coordination units which receive and register orders from different customers. The coordination units distribute the orders to production units. The various units are updated by data replications in conjunction with changes to system functions, system application and system structure. The data contained in the databases of the production units are entered in memory elements which are arranged for accessing program contents when executing data replications via one or more interfaces. In the arrangement described, a production job for a particular dental product is assigned to a particular production unit by one of the coordination units. The data is then replicated from the coordination unit to that particular production unit.
There are some practical disadvantages associated with such an arrangement. For example, if a particular production unit becomes disabled or inoperative after assignment of the production jobs, the production jobs have to be re-assigned to another production unit. Further, when manufacturing dental prostheses, it is desirable to tailor the machining of the prosthesis to the material characteristics of the material to be machined. To this end, a particular material blank having certain material characteristics may be assigned to a particular prosthesis or production job. If the production job is assigned to a particular production unit for machining, the operator has to make sure that the material blank is placed in the production unit assigned to that production job. If the material blank is placed in the wrong production unit, delays would be caused in the manufacturing process.
Hence, there is a need for a more flexible and robust method and system for manufacturing dental prostheses in an environment having a plurality of production devices. It would be advantageous to provide a system in which it is not necessary to allocate a particular production unit for a particular production job, so that inconveniences associated with such allocation can be eliminated and production jobs can be done in a more autonomous fashion.